A free program for Android, by Ping Identity Corporation.
End-to-end mobile strong authentication
When an end user wants to log in to their applications, they need to provide a username and password. But that doesn't mean the end user needs to remember the combination. In fact, in many cases, it is much easier for the end user to just touch a button on their device and get a one-time security code. End-to-end mobile strong authentication is built on the concept of one-time security codes. End-users are presented with a notification on their device when strong authentication is needed and offers offline support when the device does not have a signal.